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TROPICAL STORM LILI DISCUSSION NUMBER  32
NATIONAL WEATHER SERVICE MIAMI FL
11 AM EDT SUN SEP 29 2002
 
AIRCRAFT FIXES OVER THE PAST 12 HOURS INDICATE LILI HAS MOVED 
WESTWARD...WITH SOME WOBBLES IN THE TRACK. DEEP CONVECTION HAS 
DEVELOPED AROUND THE LOW-LEVEL CENTER AND RECON DATA INDICATES AN 
8-11 NMI DIAMETER EYE HAS FORMED. THE HIGHEST 850 MB FLIGHT-LEVEL 
WIND REPORTED THIS MORNING HAS BEEN 57 KT...EQUAL TO ABOUT 46 KT AT 
THE SURFACE...AND A MINIMUM PRESSURE OF 994 MB. UPPER-LEVEL OUTFLOW 
REMAINS GOOD IN ALL QUADRANTS WHILE OUTER CONVECTIVE BANDING 
FEATURES HAVE IMPROVED.
 
THE INITIAL MOTION ESTIMATE IS 270/06...EVEN THOUGH LILI HAS MADE A 
SLIGHT WOBBLE TO THE SOUTHWEST OVER THE LAST TWO RECON FIXES. SINCE 
THE LOW-LEVEL STEERING FLOW IS WEAK...LILI MAY JUST BE DOING A 
SEEING-EYE TRICK BY WOBBLING JUST OFFSHORE THE NORTH COAST OF 
JAMAICA. HOWEVER...ONCE LILI CLEARS THE WESTERN END OF JAMAICA...A 
GOOD SOUTHWESTERLY SURGE THAT IS SEEN DEVELOPING SOUTH OF JAMAICA IN 
SATELLITE IMAGERY AND QUIKSCAT DATA WILL PROBABLY ACT TO JOG THE 
CYCLONE NORTHWARD A LITTLE. BEYOND 12 HOURS...LILI IS EXPECTED TO 
TRACK WEST-NORTHWESTWARD AROUND THE SOUTHERN PERIPHERY OF THE 
SUBTROPICAL HIGH THAT IS FORECAST TO GRADUALLY STRENGTHEN AND PUSH 
WESTWARD ACROSS FLORIDA AND THE SOUTHEAST U.S. THROUGHOUT THE 
FORECAST PERIOD. DUE TO THE MORE WESTWARD JOG THAT LILI HAS TAKEN... 
ALL OF THE NHC MODEL GUIDANCE HAS SHIFTED WESTWARD ACCORDINGLY. THE 
UKMET AND NOGAPS MODELS ARE ON THE FAR WESTERN EDGE OF THE MODEL 
SUITE...WHILE THE AVN/GFS AND AVN/GFS ENSEMBLE MODELS ARE ON THE 
EASTERN EDGE OF THE GUIDANCE ENVELOPE. THE GFDL IS JUST LEFT OF THE 
AVN/GFS MODEL...WHEREAS THE GFDN IS CLOSE TO THE UKMET-NOGAPS 
SOLUTIONS. THE OFFICIAL FORECAST TRACK WAS ADJUSTED TO THE LEFT OF 
THE PREVIOUS TRACK AND IS SIMILAR TO THE GFDL IN DIRECTION...BUT 
SLOWER LIKE THE AVN/GFS. AFTER 48 HOURS...THE FORWARD MOTION WAS 
INCREASED TO ABOUT 11 KT LIKE THE AVN/GFS MODEL...WHICH IS THE 
SLOWEST OF ALL THE GLOBAL MODELS.

THE INTENSITY FORECAST IS SOMEWHAT PROBLEMATIC. GENERALLY...WHEN A 
MODERATE TROPICAL STORM DEVELOPS A SMALL DIAMETER EYE...RAPID 
INTENSIFICATION USUALLY FOLLOWS. HOWEVER...THE PROXIMITY TO LAND 
WILL LIKELY PRECLUDE THAT FROM HAPPENING...AT LEAST FOR THE NEXT 12 
HOURS OR SO. BUT BEYOND THAT...UPPER-LEVEL CONDITIONS APPEAR VERY 
FAVORABLE FOR SOME SIGNIFICANT STRENGTHENING TO OCCUR BEFORE LILI 
MAKES AN EXPECTED LANDFALL OVER WESTERN CUBA. AS WAS ALLUDED TO IN 
THE PREVIOUS DISCUSSION...LILI HAS THE POTENTIAL TO BECOME A 
SIGNIFICANT HURRICANE ONCE IT MOVES INTO THE SOUTHEAST GULF OF 
MEXICO. HOWEVER...THE OFFICIAL INTENSITY FORECAST IS NOT QUITE AS 
ROBUST AS THE SHIPS INTENSITY MODEL...WHICH BRINGS LILI TO 91 KT IN 
72 HOURS.
 
FORECASTER STEWART
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL     29/1500Z 18.7N  77.6W    45 KTS
12HR VT     30/0000Z 19.2N  78.5W    50 KTS
24HR VT     30/1200Z 20.2N  80.0W    55 KTS
36HR VT     01/0000Z 21.2N  81.8W    65 KTS
48HR VT     01/1200Z 22.4N  83.8W    70 KTS...INLAND OVER WRN CUBA
72HR VT     02/1200Z 24.5N  87.5W    80 KTS
 
 
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